A pediatric case of tubulointerstitial nephritis and uveitis syndrome

Abstract

Tubulointerstitial Nephritis and Uveitis Syndrome (TINU Syndrome) is a rare entity of unknown origin. Most cases described affect adolescents and women. It often implies a renal biopsy and is established upon the presence of uveitis and tubulointerstitial nephritis in the same patient, after all possible causes are excluded. The authors report the case of a 12-year-old teenage boy with nausea, vomiting, and weight loss lasting two weeks, taken to his local hospital with acute kidney injury, oliguria, and high blood pressure. After transfer to a specialized centre and exclusion of infectious, toxic, and autoimmune causes, intravenous and oral corticosteroid therapy was started. Renal biopsy confirmed interstitial nephritis of undetermined aetiology and the patient was discharged after favourable restauration of renal function, with a course of 4 weeks of steroids and progressive decrements over 10 weeks. Four months after the onset of the condition, the teenager was taken to the hospital with eye redness and tenderness. Bilateral anterior uveitis was described, which established the diagnosis of TINU Syndrome. After two years of joint follow-up by Paediatric Nephrology and Ophthalmology, the patient remains stable, without relapses, or ocular or renal sequelae.